Real-space study of monolayer hBN encapsulated bilayer MoTe₂ devices

Molybdenum ditelluride (MoTe₂) has recently emerged as a quantum material platform, especially exhibiting the fractional quantum anomalous Hall (FQAH) effect and unconventional superconductivity in its twisted bilayer configuration. However, a deep understanding of the strong many-body correlations and superconductivity in this system requires systematic real-space studies of the electronic and structural properties of few-layer MoTe₂ by scanning tunneling microscopy (STM). This remains challenging due to the high air-sensitivity of MoTe₂ and the difficulties associated with STM device fabrication. Here, we adopted an encapsulation strategy employing monolayer hexagonal boron nitride (hBN) that enabled atomic-scale characterization of air-sensitive MoTe₂ devices via scanning probe techniques. This approach allowed us to probe both natural and twisted bilayer MoTe₂ (tMoTe₂) (with twist angle θ=2.35∘) directly while preserving their intrinsic electronic states. Our high-resolution scanning tunneling spectroscopy (STS) measurements detected the extremely weak valence band at the K-valley, in agreement with large-scale density functional theory (DFT) calculations. This work not only establishes a framework for studying air-sensitive quantum materials but also provides fundamental insights into moiré-engineered correlated and topological states in van der Waals heterostructures.